Dwarven Dread (Pathfinder)

From publisher blurb:

Four to six PCs of levels 5-6

Argyle the Betrayer was a powerful Dwarven cave wizard that was corrupted by a Derro Magister named Angree’, and is now quite insane and bent on the destruction of the surface races, most especially Dwarfs. Angree’ has subjugated Argyle using powerful hallucinogens, in addition to a number of Duergar Tyrants, and positioned Argyle as a mad savior to the Duergar. Argyle and his “servant” Angree’, as well as the Duergar, spend most days torturing Dwarfs, or calling on elementals to forge alliances to overthrow the surface dwellers.

Argyle’s complex is found miles below the surface off a well-traveled path in the Underworld. Its walls are covered in a fungus that emits an eerie green glow.